FIG. 1 is a schematic diagram showing a configuration of a wet etching machine used in flat display panel manufacturing according to the prior art. The etching machine includes an inlet buffering chamber 1, an etching chamber 2, a cleaning chamber 3, and an outlet buffering chamber 4, which are successively connected in series. The etching chamber 2 is also comprised of multiple chambers connected in series. A substrate 5 to be etched successively moves through each chamber of the etching chamber 2 for completing the etching process. The total time of the etching process is the time of the substrate passing through each of the chambers of the etching chamber 2.
However, in actual manufacturing, the required etching time of one substrate is often longer than the total transfer time of the substrate passing through each of the etching chambers without stopping the substrate. Due to the lower speed limit of transferring the substrate, the slower the substrate moves, the higher the possibility of making the substrate slip. The etching time therefore is extended due to the substrate needs to be stopped in the etching chamber, so that elongate the takt time and accordingly lower the production capacity. Further, when the total etching time required by manufacturing is longer than the transfer time of the substrate without stopping the substrate, another method in the prior art is to increase the number of the etching chambers connected in series, so as to prolong the transfer time of the substrate moving through the etching chambers, therefore increasing the total etching time and making the substrate no longer needs to stop, so that achieving the purpose of speed up the takt time. However, when increasing the number of the etching chambers connected in series, the area of the facility will be increased correspondingly. The larger the substrate, the more area of the facility will increase, and may need to build more clean rooms and increasing operation cost. Thus, this method is not an effective solution to solve the above-described problem.